Mill Creek Sink Nature Preserve (Alachua Sinks)
Alachua County, Florida
In 1993, the NSS accepted the donation of Mill Creek Sink, which is a completely water-filled cave. The surface stream system is dissected by more than 10 swallow holes that divert water underground, draining a basin of more than 70 square miles. The sinkhole slopes steeply nearly 50 feet down to the water’s edge. The sinkhole is filled with very dark, tannic-stained water for most of the year, as well as fallen trees and debris. Clear water is not encountered for a considerable distance into the system. The main cave system has tunnel both upstream and downstream with depths known to 227 feet.
Mill Creek Sink is home to turtles, both soft-shell and snapping varieties. Alligators are occasionally seen also. Brim and catfish are seen in the basin and catfish have been spotted throughout the cave system. Blind cave crayfish, the Pallid Cave crayfish (Procambarus pallidus), the Florida Cave Amphipod (Crangonyx grandimus) and the Hobb's Cave Amphipod (Crangonyx hobsi) are also found in the cave and are "species of special concern" designated by the State of Florida. The Florida Committee on Rare and Endangers Biota of Florida has published the selected information for State of Florida Game and Freshwater Fish Commission. This information supports and recommends protection of these and other related cave species.